Spatial relationships between surface ruptures in the Ms 8.0 wenchuan earthquake, the longmen shan region, Sichuan, China

摘要

During the Ms 8.0 Wenchuan Earthquake of May 12, 2008, three distinct faults in the Longmen Shan along the eastern margin of the Tibetan Plateau ruptured. We have carried out detailed field geological mapping on these faults (the Yingxiu-Beichuan, the Pengxian-Guanxian, and the Xiaoyudong Faults), as well as the minor Leigu Fault, using GPS and total station surveys. The surface rupture of the Wenchuan Earthquake consists of two margin-parallel thrust faults linked by the Xiaoyudong tear fault. By comparing the features of the surface rupture of the faults, the spatial relationships between the different surface ruptures can be determined. It is clear that the margin-parallel thrust faults are linked at depth, forming an imbricated thrust linked by a tear fault.